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Basic - Turn on the light by press and release the on/off button switch (<0.4s). To turn off the light, press and release the switch again.
For momentary on, press and hold the button switch for immediate output.
Twist the head to select between four output levels. You can pre-select the desired output level before turning on the flashlight.
Instant Turbo output - at any output level, press and hold the flashlight for 100% output. Release the button to return to previous level.
Instant Strobe output - at any output level (or off), double press and hold the on/off button switch for strobe output. Release the button to return to previous level (or off).
To access auxiliary levels, starting at head tight position (1st level), loosen to 3rd or 4th level and then tighten the head within one second to enter auxiliary setting. Repeat to cycle through all settings. Turn off the light or loosen the head to quit.
(Programmable Features) Mode switching: To switch between tactical and regular mode, turn on the flashlight at 1st level, dial to 2nd level and then back to 1st level for ten times within five seconds.
(Programmable Features) Energy saving feature: Enabled by default, this feature reduces output current by 25% (or 10% when disabled) after 200 seconds at turbo mode. To toggle this feature, turn on the flashlight at 4th level, and dial to 3rd level and then back to 4th level for ten times within five seconds.

Includes everything in base mode, plus:
(Extra) signal connection through the body tube for rear accessories add-on
(Extra) tailcap w/ switch and tail-standing ability
Flashlight head come with front-mount thread for bezel and filter attachment
Stainless steel bezel
Heavy Duty Nylon Holster w/ self-retention device and open-top design
ET54 diffuser filter, ET54 yellow filter, ET54 red filter, ET54 green filter, ET54 blue filter.